He is now a schoolteacher, but Abu Mustafa admits he still sometimes has flashbacks to his 10 months in American custody at Iraq's most infamous prison -- Abu Ghraib.
"I cannot forget, and I cannot describe, the hell that I lived," said the 33-year-old father-of-two, who remains profoundly traumatised by his time there and, according to his family, has become mentally unstable.
"At times, I get crazy -- I shout for no reason, or I remain prostrate for hours. My family asks me why I act this way, but what can I say?"
Abu Mustafa, who was a member of anti-US Shiite cleric Moqtada al-Sadr's feared Mahdi Army militia, was arrested in September 2004 and spent four years in American detention facilities, including 10 months in Abu Ghraib.
"They put us in iron boxes and made deafening noises that caused severe headaches," he said, adding: "I sometimes suddenly have the feeling that they have shackled me to put me back in that box."
In April 2004, the prison at Abu Ghraib shot to international headlines and became a potent negative symbol of the US occupation to many Iraqis after evidence emerged of detainee abuse by American soldiers at the facility.
The published photographs of the abuse showed a pyramid of naked detainees stacked on top of each other, prisoners attached to leashes and threatened with dogs, or being forced to masturbate.
Washington insisted the scandal was carried out by a handful of rogue soldiers, and was not endemic. Eventually, 11 soldiers were convicted in connection to the abuse at Abu Ghraib, and received punishments ranging from an army discharge to 10 years in prison.
Then-president George W. Bush described the detainee abuse as "the biggest mistake" committed by the United States in Iraq. The prison was eventually closed from September 2006 to February 2009.
The prison, which was built by British contractors in the 1960s, was a centre of torture and execution under the regime of Saddam Hussein.
After his overthrow in April 2003, it was renamed the "Baghdad Correctional Facility" by the US, and was eventually transfered to Iraqi control in September 2006.
Signup to our newsletter and follow us on Facebook and Twitter!
According to Naji Abid Hamid, the head of Ahed (Promise), a prisoners' rights organisation, 70 percent of the tens of thousands of Iraqis that passed through US prisons suffer from physical and psychological problems.
"There are outbursts of violence; some isolate themselves from their families or refuse to eat for days, while others are divorced," he said.
In Samarra, 110 kilometres (70 miles) north of Baghdad, schoolteacher Abu Mohammed believes that he has become "anti-social."
"I no longer want to have any fun, I do not spend any time with my friends," the 47-year-old father of five said. "I feel as though my children hate me."
He was arrested in March 2004 when he was found in the area of a bomb blast against US forces. He spent two years in Abu Ghraib before he was let go.
In the former insurgent bastion of Fallujah, just west of Abu Ghraib, Mahmud Ali Hussein remains bitter at his detention by US forces which inadvertantly caused him to lose all his limbs when they were blown off in an attack on the American convoy transporting him to the prison.
"Never -- I will never forget that the Americans made me this way," he said.
In October 2005, as Iraq's violent insurgency was reaching its peak, he was detained by American troops while he was in his father's garage in Fallujah. Along with 10 others, he was taken to Abu Ghraib. He was eventually freed in June 2006.
"The American soldiers treated prisoners brutally," the 35-year-old said, seated in his wheelchair. "Even the sick were tied to their beds, and when prisoners were transferred to different sites, their hands and feet were chained together."
While he spoke, one of his parents placed a cigarette between Mahmud's lips and lit it, holding it in place to allow him to take a drag.
"I wish I still had my arms and legs, so I could fight and help my long-suffering people," he said, speaking in the garden of his family home with his parents as they looked at pictures of their son, before he lost his limbs.
As they went through the photos, Mahmud's father Ali Hussein stood up and, almost without emotion, said: "If there is such a thing as international justice, these Americans would be tried and sent to prison."
"I hope they receive the same fate as my son," he said.